What is a blockage of a pulmonary artery by foreign matter?
The obstruction may be fat, air, tumor tissue, or a thrombus that usually arises from a peripheral vein (most frequently arising from the deep veins of the legs)

Pulmonary Embolism

A blood clot that forms and remains in a vein is called what?

a thrombus

A blood clot that becomes dislodged and travels to another part of the body is called what?

an embolus

Embolus may originate from one large thrombus or occur as a series of small thrombi and may or may not interfere with what?

the right side of the heart's ability to perfuse the lungs adequately

If Blockage of the pulmonary vascular system is significant blood flow restricted leading to what?

Pulmonary infarction

Alveolar atelectasis

Alveolar consolidation

Tissue necrosis

Can a pulmonary embolism cause bronchoconstriction or bronchospasm?

YES

Exact mechanism not known. Maybe release of histamine, prostoglandin or other cellular mediators

Hypoxemia

Hypercapnia

The most common cause of pulmonary blood clots for Pulmonary Embolism originate�or break away from�?

deep vein thrombus (DVT)

What are other possible causes of thrombosis or embolism?

Fat

Air

Amniotic fluid

Bone marrow

Tumor fragments

What does Virchow's triad include?

Thrombosis

Blood Flow

Vessel

with Thrombosis being in the middle

Blood clot formation is due to three things, what are they?

Blood � the increased tendency of blood to form clots

Vessel Wall � injury to the endothelial cells that line the vessels

Blood Flow � slowing or stagnation of blood flow through the veins

Blood � the increased tendency of blood to form clots is referred to as what, and what usually will caused this?

hypercoagulability

Deficiencies of anticoagulants

Protiens

Increases in clotting factors in the blood

Prothrombin G20210A

Polycythemia

How does Vessel Wall pertain to the formation of a thrombus?

injury to the endothelial cells that line the vessels

What produce chemicals that inhibit the clotting of platelets inside the vessels?
Breakdown or absence of the cells allows clots to form in its place.

epithelial cells; from endothelium

How does Blood Flow pertain to the formation of a thrombus?

slowing or stagnation of blood flow through the veins

If blood flow slows (venous stasis) it allows platelets more time in contact with endothelium making it more likely that clots may form

How is Venous stasis a risk factor for Pulmonary Embolism?

Inactivity (most common)

Prolonged bed rest

Prolonged sitting

Congestive heart failure

Varicose veins

Thrombophlebitis

How do Surgical Procedures pertain to Pulmonary Embolism? (name examples)

It is a risk factor

Hip surgery

Pelvic surgery

Knee surgery

- these last three are most important because they limit mobility for extended amount of time

Certain obstetric or gynecologic procedures

How does Trauma pertain to pulmonary embolism? (name examples)

risk factor

Bone fractures

Extensive injury to soft tissue

Postoperative or postpartum states

Extensive hip or abdominal operation

Phlegmasia alba dolens puerperarum

How do Hypercoagulation disorders pertain to pulmonary embolism? (name examples)

Increased second heart sound (S2) due to increased pressure in the pulmonary artery � valve closes more forcefully

Increased splitting of the second heart sound (S2) sometimes noted due to either (1) pulmonary hypertension or (2) incomplete right bundle branch block (delay of signal sent to right slowing contraction)

Third heart sound (or ventricular gallop) � exact cause unknown

What is a consequence of increased pulmonary blood pressure due to strain or hypertrophy causes a sustained lift on the left lower portion of the sternum? (part of physical exam)

Right ventricular heave or lift

A right ventricular lift can be detected in patients with a pulmonary embolism if significant pulmonary hypertension is present. When will it be felt?